Like most people (probably), I keep mine in my wallet with my drivers license and insurance card. I save it just in case I ever accidentally run someone over- someone runs on front of me, some kid goes chasing after a ball. But (probably also like most people), I never end up using it for that reason, and instead join the ranks of all the people too old to actually go out a commit a crime.

So, I guess in the end I don't file my taxes and no one can do a damn thing about it!